The SSH (Secure Shell) is a more secure replacement for telnet, rlogin, rsh, rcp, and ftp.
A non-commercial version of SSH Secure Shell for Servers (Unix/Linux) is available in source-code on the web. You can download version 3.1 from the Ole Miss IT Helpdesk web site, download version 3.2.9 or get the latest version from the SSH Web Site (although it is no longer free from there.) Macintosh users are not currently supported directly, but a number of third-party client solutions are available for both SSH1 and SSH2. Nifty Telnet is a secure shell client for the MacIntosh, and can be downloaded from the IT Helpdesk.